W123-TECH Electric Window Switches

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I was bombing around in the red baron this weekend (1984 euro 300D, 4-spd with euro headlights and small bumpers) and my windows went crazy on me.
It was hilarious. As I would raise the drivers side window, the passenger side would open and visa versa. I could only get one closed and drove home that way.
I tried to uncross the wires connecting to the switches and was surprised that the wires seem to cross connect to each other. And there sure are a lot of them.
I know it's an easy fix, but it was beyond my skill and patience and it was getting to be miller time, so I garaged the beast .

I neglected to remember that when we brought the car to US I had the front two windows converted from manual to electric by the federalizer. I see a bunch of black electricians tape under there. It could be a shoemaker job, that lasted 20 years.
Question,
Would the motor installation necessairily eliminate the use of the hand crank method, if I put back the crank handles ?

Is there a documented procedure for testing the switches, such as taking them out of the circuit and using an Ohm meter to check for continuity across certain poles while the switch is in Up or Down position? I have read several posts both in the Diesel forum and in this one that discuss replacing the switches and disassembling the switches to clean the contacts, but I would prefer to diagnose that there is a problem with the switch before doing either of those things.

Have fooled around with mine several times. Don't need meters. Can do it by interchanging switches between doors, to determine if the switch is bad.

Are the switches in the center console working OK? Or is one of these switches not working. If that's the problem, the right and left dual switches are interchaneable. So you can find out which switch is bad. Be careful when removing the switch to label the wires. The wires are rather short, so removing and reinstalling the console switches needs to be done with some finesse.

If both console switches are OK then you have to interchange switches between opposite doors to tell if the switch is bad.

Once you remove the bad switch, it can be taken apart and the contacts cleaned. Though it's a tricky bit of surgery because the switch is intended to be replaced rather than repaired. Replacement switches are inexpensive so I would recommend not bothering with cleaning the contacts, unless you are one of those people who want to keep the ORIGINAL parts.

My rear power window no longer goes up or down. The window appears to be getting power. It just makes a faint banging noise like a tiny machine gun...bap-bap-bap-bap-bap! The other rear window works intermittantly. The panel which contains the switches is quite loose but I don't think this is related to the gunning sounds. It does have something to do with the second window's aliments. Any ideas?

Yep I actually found a guy selling everything to convert my 300D over to manual.
everything came off a rusty 240D including excellent door panels.
Best fix I've done yet and I wont miss those electric ones since they never work all that well anyways.
I should have grabbed the manual sunroof while I was there.